In case you missed it, please see Re^5: Avoiding compound data in software and system design. The salient passage is:

To achieve all that, you'd need more than just a hash. You'd need one flag per field to decide whether the key name should be prepended to the fields value. You'd need another value to ensure ordering. You'd need yet another flag to ensure that (for example) backslashes in pathnames got escaped for interpolation.

Though the context of the post makes that clearer.